The effect of polyaniline electrode doped with transition metal ions for supercapacitors

Abstract

AbstractDoping transition metal ions into polyaniline (PANI) as an attractive electrode material have been regarded as one of the crucial factors to improve the capacitive performance and the cycle stability of supercapacitors due to their excellent metal properties and good conductivity. Herein, PANI has been prepared via in situ facile and low‐cost electro‐polymerization method. At a current density of 0.2 A g−1, the supercapacitor using PANI electrode shows the specific capacitances of 203.0 F g−1 in 1 M H2SO4 electrolyte. To further improve the electrochemical activity of PANI electrode, the transition metal ions M2+ (M2+ = Ni2+, Co2+, Mn2+, and Cu2+) have been doped into PANI electrode via the same electro‐polymerization method. And the supercapacitor with the different doped‐PANI electrode generates the specific capacitances of 364.3, 326.1, 258.5, and 250.6 F g−1 respectively from PANI‐Ni2+, PANI‐Co2+, PANI‐Mn2+, and PANI‐Cu2+, which were superior to 79.5%, 60.6%,27.3%, and 23.4% of the pristine PANI based counterpart under the same test conditions and method. The favorable performances make the different doped‐PANI act as a new resource of the high performance electrode materials of supercapacitor.